A roll stand has a pair of working rolls at least one of which during normal use is carried on a roll shaft that passes through a central hole in the one roll. One axial end of the roll shaft is detachably connected to a drive shaft via a coupling. A roll-changing device is associated with the roll stand.
It is known to change rolls in a standard roll stand according to the following procedure: The roll, together with associated parts, namely the roll shaft and the end mounts, is removed from the frame of its roll stand in order to exchange or replace the roll at a location at some distance from the rolling line.
Usually an end mount is pulled off the roll and gotten out of the way, then the roll is pulled axially off its shaft. Another roll is slid onto the shaft, and the end mount, normally comprised of a bearing around a stub end of the shaft and a block in which an outer race of the bearing is set, is reinstalled. Offline roll-changing devices are often used to assist in changing the roll. After the roll has been switched, the entire unit is then reinstalled in the forming machine.
Changing the rolls in a standard roll stand requires a considerable amount of time, during which the machine is not available. This is associated with an economic loss. The changing procedure also involves substantial effort in handling.